"The latest talks between the Syrian and Iraqi side have been crowned by declaring a new era with the participation of the Syrian brothers in working on the security and stability with Iraq," he told the Associated Press news agency.

Mr Zebari said the two sides had also agreed to cooperate on security issues.

They also agreed to allow US forces to stay in the country until they were no longer needed.

White House National Security Council spokesman Gordon Johndroe said the US had always encouraged Iraq's neighbours to assist its government.

"Syria needs to now demonstrate that it is committed to constructive engagement and fostering an Iraq that can govern, sustain and defend itself," he told AFP news agency.

The move comes as efforts to involve Iran and Syria in stabilising Iraq appeared to be gaining momentum.

Earlier, the Iraqi president, Jalal Talabani, accepted an invitation to go to Iran on Saturday.

There are reports that the Syrian president, Bashar al-Assad, may also go to Iran, but there has been no confirmation from Damascus.

US 'more amenable'

The US administration gave a cautious welcome to news that the Iraqi president would be visiting Iran, but analysts say the US government has been more amenable to regional diplomacy since heavy losses for President George W Bush in 7 November mid-term elections.

HAVE YOUR SAY

Perhaps outside influence from Syria and Iran can show Iraqis the way to peace amongst themselves